**4. Public health significance of campylobacteriosis**

Campylobacteriosis is continuously a serious public health concern, especially in developing countries. The incidence of campylobacteriosis is substantially increased in the last couple of decades with a high morbidity rate and significant infant mortality. Moreover, emerging new species and antibiotic resistance in most common species, including *Campylobacter jejuni* are additional challenges in the control of *Campylobacter* infections [43]. A serious methodological effort is required for public awareness and disease control with the involvement of all stakeholders. Primarily, a continuous ongoing surveillance program is required with proper laboratory infrastructure for the diagnosis along with fundamental and effective enteric disease control programs, especially in developing countries. Further, a systematic approach is required to control *Campylobacter* infections, including proper monitoring of disease burden, source attribution, risk assessment and management, surveillance of antimicrobial resistance, and assessment of possible control measures. However, thermophilic *Campylobacter* is ubiquitously present, but most recent outbreaks were commonly associated with water and food cross-contamination with animal shedding. Although, animals are asymptomatic carriers of *Campylobacter*, cross-contamination of the food chain with animal waste at the different stages of slaughtering, processing and marketing, direct human contact with pets, and contamination of drinking water with animal excreta possibly lead to disease outbreaks in human [3]. Indeed, *Campylobacter* spp. and sources of food chain contaminations should also be taken into account while developing disease control strategies.

#### **4.1 Burden of the disease and risk assessment**

The disease burden is difficult to predict in the case of campylobacteriosis. Population-based cohort studies are commonly used to estimate the disease burden, especially in developed countries. According to the two population-based cohorts, the incidence of gastroenteritis due to *Campylobacter* spp. was one out of seven and one

out of four people in the UK and Netherlands, respectively [43]. Cohort-based studies are more common than population-based studies.

Campylobacteriosis accounts for 7.5 million DALY (disability-adjusted life years) or 8.4% of the global burden of diarrheal diseases, according to the Global Burden of Disease (GBD) project, and ranks fourth among identified pathogens after rotavirus (18.7 million DALY), typhoid fever (12.2 million DALY), and cryptosporidiosis (8.3 million DALY) [44]. Estimating disease burden enables the implementation of potential biosafety or control measures as well as the evaluation of the disease and/or outbreak situation in specific population areas.

#### **4.2 Source attribution and risk assessment of** *Campylobacter* **infections**

The disease source and transmission routes are also assessed with microbial source attributions. *Campylobacter* spp. are isolated from human infections, and gene sequences are compared with *Campylobacter* spp. isolated from food and environmental sources. Similarly, a multilocus sequence typing (MLST) is used for the source attribution in the epidemiological investigation of rural and urban populations of New Zealand [45] and the United Kingdom [46], which indicated that both populations have different epidemiological patterns of *Campylobacter*. The cost of annual disease attribution is still very high. According to an estimate, the annual attribution cost of *Campylobacter* infections among other diarrhoeal diseases in the USA is approximately 1.2–4 billion USD per year [47, 48] and 2.4 billion EUR in the EU [49]. Therefore, the estimation of disease burden is constantly becoming an important parameter to assess disease risk and to develop an effective health care policy. However, a unified and consistent risk assessment plan is extremely desirable in campylobacteriosis. Previously, cross-contamination of the food chain with *Campylobacter* from poultry carcass has been successfully estimated with two mathematical risk assessment models [50], which indicates that human incidence of Campylobacteriosis is reduced up to 30 times with 2 log reduction of the *Campylobacter* number on poultry carcass. However, a unified accurate quantitative risk assessment model is difficult to develop in this disease due to the continuous emergence of genetic variation in *Campylobacter* spp., the subsequent diverse range of virulence, and different host-immune defenses [3]. However, several previous studies indicate that cross-contamination of the food chain from poultry carcasses is the most common source of human infections of *Campylobacter*. The control of poultry-born *Campylobacter* cross-contamination in the food chain can be one of the potential control measures to reduce the human incidence of campylobacteriosis.

#### **4.3 Risk management and control measures**

The risk management plans should be implemented according to the species of *Campylobacter* infections, disease source, and risk assessment recommendations. The reduction of bacterial numbers in poultry carcasses, the most common cause of campylobacteriosis, can be achieved with strict biosecurity measures in poultry flocks, appropriate slaughtering procedures, and hygienic meat processing methods. On other hand, bacteriophage can also be used to reduce pathogenic bacterial numbers in food chains. Previously, the reduction of bacterial count in the food chain up to the magnitude of two has been successfully achieved by the application of bacteriophage [51]. Additionally, physical and chemical decontamination and disinfection methods can also reduce the bacterial number in poultry carcasses and subsequently incidence

#### *Pathobiology, Public Health Significance, and Control of* Campylobacter *Infections DOI: http://dx.doi.org/10.5772/intechopen.112216*

of campylobacteriosis. Further, the continuous surveillance of *Campylobacter* spp. against different antimicrobial agents should also be monitored and the impact of antimicrobial use should also be regularly assessed in the risk assessment and disease attribution process [52]. Public health authorities should also introduce public awareness programs about different sources of *Campylobacter* infections, health impacts, and possible control or safety measures. The increasing incidence of campylobacteriosis in developing countries [53] further indicates the need for accurate disease surveillance along with strict food safety regulations followed by alleviation strategies to control *Campylobacter* infections in these areas. The economic burden to implement mitigation strategies is an additional hitch in the control of campylobacteriosis in these countries. However, a hygienic food chain supply, safe contact with pet animals, and public awareness program about *Campylobacter* infections can collectively improve the epidemiological prevalence and public health in developing countries.
